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    <title>Document</title>
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    <script>
      function getDays(params) {
        console.log(isRunYear(params));
      }
      function isRunYear(year) {
        if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
          console.log(year + " is run nian");
          return 29;
        }
        return 28;
      }
      getDays(2000);
    </script>
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